Rotary valve cam engine

ABSTRACT

A rotary valve cam engine of the type described in U.S. Pat. No. 3,456,630, in which the overall length of the engine along its principal axis is substantially shortened by providing the reciprocating plates which transmit motion from cylinder connecting rods to the main cams with a centrally disposed opening, and positioning the cams within the opening, such that during reciprocation, the entire longitudinal path of travel lies within the length of the cam. Means is also provided to accommodate for guide rod alignment with the occurrence of differential thermal expansion between the cylinder block and the reciprocating plates. An improved cam follower construction permitting higher operational speed is provided.

United States Patent [191 Karlan Apr. 23, 1974 ROTARY VALVE CAM ENGINE Primary Examiner-Charles J. Myhre [76] Inventor: Paul Karlan, 620 Ogden Ave., Ass'smm Exammer :rny Argenbnght Mamamneck 10543 Attorney, Agent, or Firm-Charles E. Temko [22] Filed: Nov. 1, 1972 57 B A [21] Appl. No.: 302,823 A rotary valve cam engine of the type described in I US. Pat. No. 3,456,630, in which the overall length of the engine along its principal axis is substantially 2% 5 123/58 2 1 4 3 2 shortened by providing the reciprocating plates which E d AB 58 AA transmit motion from cylinder connecting rods to the l 0 "123/58 AM 9 193 main cams with a centrally disposed opening, and positioning the cams within the opening, such that during reciprocation, the entire longitudinal path of travel [56] References Cited lies within the length of the cam. Means is also pro- UNITED STATES PATENTS vided to accommodate for guide rod alignment with 3,456,630 7/1969 Karlan 123/58 AM the occurrence of differential thermal expansion be- FOREIGN PATENTS OR APPLICATIONS giveen the cycllinder block and the reciprocating plates. n improve cam o ower construction permitting 323,33; 3/1935 France 123/58 A higher Operational Speed is provided 8/1937 France 123/58 AB 3 Claims, 4 Drawing; Figures ROTARY .VALVE CAM ENGINE This invention relates generally to the field of rotary valve cam engines of the type disclosed in my prior U.S. Pat. No. 3,456,630 granted July 22, I969, andmore particularly to an improved construction permitting the configuration of the engine to be materially shorter along its principal axis, thereby facilitating installation in relatively small areas. Additionally, the improved construction permits a relatively wide bore-short stroke ratio, permitting the engine to operate atsubstantially higher rotational speeds.

BRIEF DESCRIPTION OF PRIOR ART US. Pat. No. 1,788,140 granted Jan., 1931 to Woolson discloses a cam type engine of the subject type. My priorU.S. Pat. No. 3,456,630 mentioned hereinabove discloses a rotary valve cam engine in which a pair of cylinder blocks align opposed pairs of cylinders in which pistons are mountedto reciprocate in opposite directions, so that the engine is essentially constantly in dynamic balance. .A rotary valve carried byithe motion output shaft which passes through the blocks is divided into fourquadrants corresponding to the normal intake, compression, power and exhaust strokes of four cycle engines. The connecting rods extending outwardly from thepistons are anchored in a reciprocating plate, the plate carrying cam followers which act upon a barrel type cam on the outer sides of each cylinder block, and the engine is characterized in that as contrasted with conventional internal combustion engines, one powerstroke of any cylinder results in a single revolution of the motion output shaft Prior designs of this type, as exemplified in my above mentioned prior patent have resulted in an engine of inordinate length along the axis of the motion output shaft, in relation to the other dimensions, and have restricted the use of the engine in that with such dimension, it is not readily installable in limited engine room space, as for example, in small power boats and the like. In addition, because of the location of the cam followers which transmit motion from the pistons to the barrel cam, engines of this type have tended to be relatively long stroke which limits the maximum rotational speeds obtainable, and consequently, the total horse power available. It is to be appreciated that this power limitation is worsened by the fact that, as mentioned above, one power stroke of each piston results in only one rotation of the motion output shaft.

BRIEF DESCRIPTION OF THE PRESENT INVENTION Briefly stated, the invention contemplates the provision of a cam engine in which the reciprocating plate which interconnects the pistons with the barrel cam at eachend of the engine is provided with a large opening sufficient to enclose the entire barrel cam, and the cam followers are alternately mounted on opposing surfaces of the reciprocating plate, rather than on extensions disposed on a single surface of the reciprocating plates. Thispermits the barrel cams to be placed much closer to the outer ends of the cylinders, and the availability of heavier bearings enables a narrower cam profile, with a resultant shorter stroke and potential higher operational speed. As increased operating temperatures are contemplated, means is incorporated to compensate for differential thermal expansion of the cylinder blocks, as compared to that of the associated reciprocating plates.

BRIEF DESCRIPTION OF THE DRAWING FIG. 4 is a schematic transverse central sectional view showing the details of the rotary valve which comprises a part of the embodiment.

DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENT In accordance with the invention, the device, generally indicated by reference character 10, resembles in many respects that disclosed in my above mentioned U.S. Pat. No. 3,456,630. The device includes first and second cylinder blocks 11 and 12, respectively, positioned to define an interstice 13 in which a rotary valve element 14 is disposed. Longitudinal support rods 15 interconnect end plates 16 and 17, much of which is provided with a centrally disposed opening 18 mounting bearings 20 for a main drive shaft 21. Piston rods 22 extend outwardly from the block and are interconnected at an inner end to corresponding pistons 23, and at outer ends thereof to first and second reciprocating plates 26 and 27.

Each of the plates 26-27 is provided with openings 29 for the mounting of two guide rods 28 and cutouts 25 for the clearance of two rods 22 attached to the opposite plate. A large centrally disposed opening 30 ac-. commodates the main drive shaft 21 and the barrel cam 31 mounted thereon. The cam 31 provides first and second cam faces 32 and 33, respectively, which cooperate with first and second cam follower rollers 34 and 35, respectively. These are mounted on first and second surfaces 36-37 of the reciprocating plates 26-27, on opposite sides of the drive shaft 21..

As the cam faces 32 and 33 are of considerably narrower profile than generally used in the prior art, the cam follower rollers 34-35 are appreciably stronger, and are preferably attached by means of relatively heavy mounting blocks 39-40 having a bore 41 accommodating roller bearings 42 which support a shaft 43, an externally projecting portion of the shaft mounting the cam follower 34. Because of the shortening of the length dimension of the device, it :may be necessary to provide recesses 45 in the upper surface of the cylinder blocks 11 and 12 to accommodate the mounting blocks 39 during the compression and exhaust portions of an operative cycle.

It is contemplated that with higher operational speeds, the engine will operate at correspondingly higher temperatures, and it is considered desirable to provide for thermal compensating means 46 in one corner of connecting plates 26 and 27, to accommodate for the differential expansion occurring in the cylinder blocks as contrasted with that occurring in the reciprocating plates. The opposite corners are rigidly mounted. Since the guide rods 28 are carried by the block, with expansion, they will tend to spread apart from each other, and this is compensated for by providing at least one enlarged opening 47 in each plate which is of elongated configuration wherein the outer end 48 may move transversely to relieve stresses and binding of the guide rods which might otherwise occur.

Turning now to FIG. 4, the details of the rotary valve 14 are illustrated. A valve housing 50 of generally rectangular configuration is bounded by an upper edge 51, a lower edge 52, and side edges 53 and 54. Induction ports 55 communicates with a pair of carburetors (not shown), and exhaust ports 56 communicate with suitable exhaust receiving means, also not shown, such as a muffler or the like. Mounted on the shaft 21 is a rotary valve body divided into four quadrants, namely an intake quadrant 58, a compression quadrant 59, a power quadrant 60 and an exhaust quadrant 61. The peripheral surfaces 61a of the valve body are serially alignable with the induction and exhaust ports, and the planar side surfaces, one of which is indicated by reference character 62, are serially alignable with aligned ports 63 and 64 which each communicate with a coaxially aligned pair of cylinders. Note that as the exhaust quadrant becomes aligned with an exhausting port of a cylinder, exhaust gasses exit from the peripheral portion of the power quadrant in order that exhaust gasses pass through the exhaust ports at the appropriate instant.

Equalization bores 65 connect opposing cylinders so that the compression is equal in both of said cylinders and an explosion in one cylinder will substantially simultaneously ignite the charge in the opposed aligned cylinder permitting use of a single spark plug for each pair of aligned cylinders where desired. It is to be noted that in contrast with my earlier construction the bores 65 are arranged radially outward of the periphery of the rotary valve body.

I wish it to be understood that I do not consider the invention limited to the precise details of structure shown and set forth in this specification, for obvious modifications will occur to those skilled in the art to which the invention pertains.

I claim:

1. In a cam type internal combustion engine having a relatively stationary frame element, a motion output shaft having a principal axis supported for rotation in said frame element, at least one barrel cam mounted on said shaft, said cam having a continuous undulating lobe having axially opposed first and second cam faces, and cylinders surrounding said shaft and having principal axes parallel to that of said shaft, at least one reciprocating plate, the plane of which is perpendicular to the axes of said cam and cylinders and interconnected to piston rods slidably moved by pistons in said cylinders along an axis parallel to that of said cylinders, the improvement comprising: said reciprocating plate having a centrally disposed opening, said barrel cam being disposed within said opening, and being of axial length sufficient to overlie the entire path of reciprocation of said plate; first and second cam follower elements mounted on axially opposed surfaces of said plate, each contacting one of said first and second cam faces, each of said cam followers including a mounting block having an elongated bore the axis of which is parallel to the plane of said plate, a pair of bearings disposed in said bore, a shaft rotatably supported by said bearings, and having an end portion thereof projecting externally of said bore and forming a cylindrical surface contacting a cam face of said barrel cam.

2. In a cam type internal combustion engine, as defined in claim 1, the improvement comprising: said reciprocating plating being slidably carried by a plurality of parallel guide rods supported by a cylinder block, and means for compensating for differential thermal expansion between said block and said reciprocating plates.

3. Structure in accordance with claim 1, further characterized in the provision of a rotary valve unit including a valve body and a valve housing surrounding said body, and at least partially positioned between opposed pairs of cylinders, said housing having through bores communicating with aligned opposed cylinders to equalize internal pressure differentials therebetween and provide for the substantial simultaneous ignition of a charge in one cylinder upon the ignition of a charge in the other cylinder. 1 

1. In a cam type internal combustion engine having a relatively stationary frame element, a motion output shaft having a principal axis supported for rotation in said frame element, at least one barrel cam mounted on said shaft, said cam having a continuous undulating lobe having axially opposed first and second cam faces, and cylinders surrounding said shaft and having principal axes parallel to that of said shaft, at least one reciprocating plate, the plane of which is perpendicular to the axes of said cam and cylinders and interconnected to piston rods slidably moved by pistons in said cylinders along an axis parallel to that of said cylinders, the improvement comprising: said reciprocating plate having a centrally disposed opening, said barrel cam being disposed within said opening, and being of axial length sufficient to overlie the entire path of reciprocation of said plate; first and second cam follower elements mounted on axially opposed surfaces of said plate, each contacting one of said first and second cam faces, each of said cam followers including a mounting block having an elongated bore the axis of which is parallel to the plane of said plate, a pair of bearings disposed in said bore, a shaft rotatably supported by said bearings, and having an end portion thereof projecting externally of said bore and forming a cylindrical surface contacting a cam face of said barrel cam.
 2. In a cam type internal combustion engine, as defined in claim 1, the improvement comprising: said reciprocating plating being slidably carried by a plurality of parallel guide rods supported by a cylinder block, and means for compensating for differential thermal expansion between said block and said reciprocating plates.
 3. Structure in accordance with claim 1, further characterized in the provision of a rotary valve unit including a valve body and a valve housing surrounding said body, and at least partially positioned between opposed pairs of cylinders, said housing having through bores communicating with aligned opposed cylinders to equalize internal pressure differentials therebetween and provide for the substantial simultaneous ignition of a charge in one cylindEr upon the ignition of a charge in the other cylinder. 